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Silicon nanoporous pillar array and its surface copper deposition

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Chinese Science Bulletin 2005年第14期50卷 1424-1428页

作者： FU Xiaonan1,2.3, CHAI Huadou1,2.& LI Xinjian1,2.1. Department of physics, Zhengzhou University, Zhengzhou 450052. china {2.(Zhengzhou University), ministry of education, Zhengzhou 450052. china 3. Department of Mathematics and physics, Henan University of Tech- nology, Zhengzhou 450052. china Department of physics Zhengzhou University Zhengzhou 450052 China key laboratory of {2. {2. (Zhengzhou University) Ministry of Education Zhengzhou 450052 China Department of Mathematics and physics Henan University of Technology Zhengzhou 450052 China

Silicon nanoporous pillar array (Si-NPA) has been prepared by a hydrothermal etching technique. Using Si-NPA as substrate, a Cu/Si-NPA nanocomposite thin film has been obtained with immersion plating method. Morpho- logical and structural analysis indicates that Si-NPA is a typical structural composite system characterized by a triple hierarchical structure, i. e. the array of micron-sized silicon pillars, the nanopores densely distributed on the surface of the pillars, and the silicon nanocrystallites that constitute the pore walls. Cu/Si-NPA inherits the morphological character- istics of Si-NPA. The compactability of the deposited copper nanoparticles varies alternatively with the local geometrical features of Si-NPA and forms a quasi-periodical pattern. Such an experimental phenomenon is attributed to the veloc- ity dependence of the copper deposition upon the local geo- metrical features of Si-NPA. These results indicate that Si-NPA might be used as an ideal template for preparing specially patterned, structured or functionalized metal/ sili- con nanocomposite systems.

关键词：硅元素薄膜蚀刻技术电镀技术

Study on the electric double layer of a cylindrical reverse micelle with functional theoretical approach

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Science china Chemistry 2006年第3期49卷 219-224页

作者： WANG Zhengwu1,2. GUO Baomin2. ZHANG Gexin1 & YU Huixin1 1. key laboratory of Industrial Biotechnology of{2., Southern Yangtze University, Wuxi 2.4036,{2. 2. School of Chemical and material Engineering, Southern Yangtze University, Wuxi 2.4036,{2. 1. key laboratory of Industrial Biotechnology of{2. Southern Yangtze University Wuxi 214036 China 2. School of Chemical and material Engineering Southern Yangtze University Wuxi 214036 China

The iterative method in functional analysis is applied to looking for asolution of the Poisson-Boltzmann equation in order to describe the problems of the distribution ofthe potentials in the electric double layer (EDL) inside the water pool for a cylindrical inversemicelle. Potentials as a function of the position of a particular point in EDL are computed, whichdisplay a quantitative agreement with those from earlier calculation of Debye and Huckel in the caseof low potentials. But it is also shown that in the higher-potential range the iterativecalculations can give more accurate results. These results indicate the utility of this functionalanalysis technique in the description of the properties of EDL for a cylindrical inverse micelle.

关键词： cylindrical reverse micelle, electrostatic double layer, Poisson-Boltzmann equation, functional analytic theory.

Two-dimensional thermoelasticity solution for functionally graded thick beams

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Science china(physics,Mechanics & Astronomy) 2006年第4期49卷 451-460页

作者： Lü Chaofeng1, CHEN Weiqiu1 & ZHONG Zheng2.1. Department of Civil Engineering, Zhejiang University, Hangzhou 31002., china 2. key {2. of Solid Mechanics of{2., School of Aerospace Engineering and Ap- plied Mechanics, Tongji University, Shanghai 2.0092. china Department of Civil Engineering Zhejiang University Hangzhou 310027 China key laboratory of Solid Mechanics of{2. School of Aerospace Engineering Applied Mechanics Tongji University Shanghai 200092 China

Two-dimensional thermoelasticity analysis of functionally graded thick beams is presented using the state space method coupled with the technique of differential quadrature. material properties vary continuously and smoothly through the beam thickness, leading to variable coefficients in the state equation derived from the elasticity equations. Approximate laminate model is employed to translate the state equation into the one with constant coefficients in each layer. To avoid numerical instability, joint coupling matrices are introduced according to the continuity conditions at interfaces in the approximate model. The differential quadrature procedure is applied to discretizing the beam in the axial direction to make easy the treatment of arbitrary end conditions. A simply-supported beam with exponentially varying material properties is considered to validate the present method. Numerical examples are performed to investigate the influences of relative parameters.

关键词： state equation differential quadrature approximate laminate model joint coupling matrices thermal stresses.

Pegmatite remote sensing extraction and metallogenic prediction in Azubai area,Xinjiang

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中国有色金属学会会刊：英文版 2011年第S3期21卷 543-548页

作者： PENG Guang-xiong1, 2. YE Zhen-chao1, 2. GAO Guang-ming1, 2. FENG De-shan1, XIONG Yun1 1. School of Geosciences and Info-physics, Central South University, Changsha 410083, china 2. {2. {2. of Metallogenic Prediction of Nonferrous Metals, ministry of education, Changsha 410083, china [a] School of Geosciences and Info-physics Central South University Changsha 410083 China [b] key laboratory of Metallogenic Prediction of Nonferrous Metals Ministry of Education Changsha 410083 China

Remote sensing technique plays an important role in geological prospecting in Altay because of the remote location and steep terrain with mountains. Pegmatite has important implications for metallogenic prospecting as most of rare metals occurs in it. Pegmatite information from optical and radar images was extracted, and the spatial distribution and scale of pegmatite were generalized in Azubai, Altay. Three mining targets, that is, Halon-Azubai, Kuermutu-Tuyibaguo and Zhuolute-Akuoyige, were delineated based on the analysis of pegmatite information, structure interpretation and other geological data.

关键词： pegmatite remote sensing information extraction metallogenic prediction

First-principles calculations on implanted TiO_2.by 3d transition metal ions

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Science china(physics,Mechanics & Astronomy) 2009年第6期52卷 838-842页

作者： HOU XingGang1,2. HUANG MeiDong1, WU XiaoLing2.& LIU AnDong2.1 Department of physics, Tianjin Normal University, Tianjin 300387, china 2.{2. {2. of Beam Technology and material Modification of ministry of education, Beijing Normal University, Beijing 100875, china Department of physics Tianjin Normal University Tianjin 300387 China key laboratory of Beam Technology and {2. Modification of{2. Beijing Normal University Beijing 100875 China

3d transition metal (V, Cr and Fe) ions are implanted into TiO2.by the method of metal ion implantation. The electronic band structures of TiO2.films doped 3d transition metal ions have been analyzed by ab initio band calculations based on a self-consistent full-potential linearized augmented plane-wave method within the first-principle formalism. Influence of implantation on TiO2.films is examined by the method of UV-visible spectrometry. The results of experiment and calculation show that the optical band gap of TiO2.films is narrowed by ion implantation. The calculation shows that the 3d state of V, Cr and Fe ions plays a significant role in red shift of UV-Vis absorbance spectrum.

关键词： 3d transition metal ions implantation TiO2 FP-LAPW electronic structure

Sediment transport capacity of hyperconcentrated flow

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Science china(physics,Mechanics & Astronomy) 2008年第8期51卷 961-975页

作者： SHU AnPing1,2.& FEI XiangJun2.1 School of Environment & key laboratory of Water and Sediment Sciences,{2. of {2.,Beijing Normal University,Beijing 100875,china 2.State key laboratory of Hydroscience and Engineering,Tsinghua University,Beijing 100084,china School of Environment & key laboratory of Water and Sediment Sciences Ministry of Education Beijing Normal University Beijing 100875 China State key laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China

As one of the most important components of river mechanics,sediment transport capacity of sediment-laden flows has attracted much attention from many researchers working on river mechanics and hydraulic engineering. Based on the time-averaged equation for a turbulent energy equilibrium in solid and liquid two-phase flow,an expression for the efficiency coefficient of suspended load movement was derived for the two-dimensional,steady,uniform,fully-developed turbulent flow. A new structural expression of sediment transport capacity was achieved. Using 115 runs of flume experimental data,which were obtained through two kinds of sediment transport experiments in the state of equilibrium,in combination with the basic rheological and sediment transporting characteristics of hyperconcentrated flow,the main parameters in the structural expression of sediment transport capacity were calibrated,and a new formula of sediment transport capacity for hyperconcentrated flow was developed. A large amount of field data from the Yellow River,Wuding River,and Yangtze River,etc. were adopted to verify the new formula and good agreement was obtained. These results above contribute to an improved theoretical system of river mechanics and a reliable tool for management of rivers carrying high concentration of sediments.

关键词： hyperconcentrated flow turbulent energy equilibrium efficiency coefficient sediment transport capacity

Discovery of double-peaking potassic volcanic rocks in Langshan Group of the Tanyaokou hydrothermal- sedimentary deposit, Inner Mongolia, and its indicating significance

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Science china Earth Sciences 2005年第6期48卷 822-833页

作者： PENG Runmin1, ZHAI Yusheng1, WANG Zhigang2.& HAN Xuefeng2.1. key laboratory of Lithospheric Tectonics and Lithoprobing Technology,{2.,{2. University of Geosciences, Beijing 100083,{2. 2. Inner Mongolia Geological Prospecting Institute, ministry of Chemical Industry, Hohhot 010074,{2. Correspondences should be addressed to Peng Runmin 1. key laboratory of Lithospheric Tectonics and Lithoprobing Technology Ministry of Education China University of Geosciences 100083 Beijing China 2. Inner Mongolia Geological Prospecting Institute Ministry of Chemical Industry 010074 Hohhot China

It is revealed that the protolith of gray-light brown potash-feldspar-leucogranulites and granulites in the 2.d formation of the LG in Tanyaokou deposit are quartz kerotophyre of synsedimentary eruption based on the following facts and features: (1) The rocks look compact and homogeneous without obvious crystals with naked eyes; (2. they contain blastoporphyritic or glomeroporphyritic and blasto-crystalloclastic crystals consisting of quartz with wavy extinction and albite with obvious alteration and deformation; (3) they also contain radiated and fibrous blasto-microspherulitic texture and swallow-tailed bifurcate and blasto-hollow-skeleton crystal texture, representing the rapid cooling characteristic of the magma during submarine volcanic eruption; (4) the major chemical compositions of the rocks are: SiO2.= 70.80%―76.00%, K2. (4.83%―6.2.%)>Na2.(2.78%―3.80%), and K2.+Na2. = 8.63%―9.00%; and (5) their petro-chemical diagrams indicate that they are volcanic rocks. Together with the characteristic that they occur in the same sequence with potassic spilite (SiO2.= 46.12.―50.68%, K2. = 4.2.%―5.93%>Na2. = 2.15%―3.14%, K2.+Na2. = 6.51%―8.08%), it can be confirmed that the vol-canics occurring in the 2.d Formation of the LG in Tanyaokou district are double-peaking potas-sic volcanic rocks. The discovery, together with the tuffs with ore minerals and the distribution of lead isotopic as well as the value of Co/Ni of pyrites >1 showing the obvious endogenic metali-zation, can prove that the Tanyaokou deposit is an untypical SEDEX-type deposit formed in the extension fault basin in the Mesoproterozonic aulacogen of the northern margin of the North china Platform, and its metallogenesis is related to the synsedimentary volcanic activities and the hydrothermal exhalation, and both the ore-forming material source and volcanics came from mantle or lower crust. These facts mentioned above, together with the meta-volcanic rocks (double-peaking) found in the Dongshengmiao and Huog

关键词： extensional rift basin, double-peaking potassic volcanic rocks, Mesoproterozoic, the 2.d formation of LG, Tanyaokou deposit, Inner Mongolia.

Effects of annealing on structural, optical and electrical properties of Al-doped ZnO thin films

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Science china(physics,Mechanics & Astronomy) 2004年第5期47卷 588-596页

作者： CHEN Yanwei1,2. YU Wenhua1 & LIU Yichun1,2.1. Centre for Advanced Optoelectronic Functional material Research, Northeast Normal University, Changchun 13002., china 2. {2. {2. of Excited State Processes, Changchun Institute of Optics, Fine Mechanics and physics, Chinese Academy of Sciences, Changchun 13002., china 1. Centre for Advanced Optoelectronic Functional material Research Northeast Normal University 130024 Changchun China 2. key laboratory of Excited State Processes Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences 130021 Changchun China

In this paper, the structural, electrical and optical properties of Al-doped zinc oxide (ZnO: Al) thin films onto quartz substrates prepared by electron beam evaporation technique were studied. All samples are polycrystal with a hexagonal structure andc-axis preferred orientation. The intense UV emissions and weak deep-level green emissions were observed. The films show high transparency, conductivity and high carrier concentration. Van der Pauw measurements show that the films are n-type degenerate semiconductor. The lowest resistivity is 6.7×10?4 Ω⊙cm at room temperature. These films exhibit a carrier density above 102. cm?3. The conduction mechanism was discussed. The behavior of metallic conduction can be observed in the high temperature range.

关键词： ZnO: Al thin film, photoluminescence, electrical properties, structural properties, Van der Pauw measurement.

Measuring-basis-encrypted six-state quantum key distribution scheme

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Progress in Natural Science:materials International 2006年第1期16卷 84-89页

作者： CHEN Pan1, DENG Fuguo1, WANG Pingxiao1 and LONG Guilu1,2.(key laboratory for Quantum Information and Measurements and Department of {2., Tsinghua University, Beijing 100084,{2. 2. key laboratory for Atomic and Molecular NanoSciences, Tsinghua University, Beijing 100084,{2.) [a]Department of physics Tsinghua University Key Laboratory for Quantum Information and Measurements Beijing China [b]Tsinghua University Key Laboratory for Atomic and Molecular NanoSciences Beijing China

A six-state quantum key distribution scheme with measuring-basis encryption technique, which is based on the six-state protocol and the MBE protocol, is proposed. In this modified six-state quantum key distribution protocol, Alice and Bob use a control key to synchronize the use of their measuring-basis so that they always use the same measuring-basis. This modified six-state quantum key distribution protocol retains the advantage of higher security and at the same time has a higher efficiency.

关键词： quantum key distribution measuring-basis encrypted six-state security.